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Oracle Latch¼°latchì¶Ü

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Oracle ¶à±íÁ¬½Ó×Ó²éѯ

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select ename,sal
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(
    select max(sal) max_sal, deptno
    from emp
    group by deptno
) t
on (emp.sal = t.max_sal and emp.deptno = t.deptno);
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